Jailed Kremlin critic Alexei Navalny on Tuesday said Russian soldiers had killed a 60-year-old man called Ilya Navalny in the Ukrainian town of Bucha apparently just because he shared Navalny's last name.
Russian forces retreated from Bucha last month and Ukrainian officials say they have discovered more than 400 bodies of people they believe were killed by Russian troops during their occupation of the area.
The allegations, which Reuters has not been able to verify, triggered condemnation from the West and fierce denials from the Kremlin, which calls the allegations a "monstrous forgery" designed to denigrate the Russian army.
Navalny shared a picture on Twitter of a passport with the name Ilya Ivanovich Navalny that he said appeared to have been deliberately left next to a dead body in Bucha.
"A completely innocent person was killed by Putin's executioners (what else can I call them? definitely not 'Russian soldiers') because he is my namesake," Navalny wrote.
"Apparently, they hoped he was a relative of mine."
The Russian defence ministry did not immediately respond to a request for comment.
Navalny said he did not know if the man was a relative but that he came from the same village as Navalny's father. He renewed an appeal to Russians to demonstrate against the war.
Millions have been forced to flee Ukraine since Russian troops invaded the country on Feb. 24. Thousands have been killed or wounded, and towns and cities have been levelled.
The Kremlin calls its actions a "special military operation" which it claims was necessary to demilitarize and "liberate" Ukraine from nationalist extremists. Kyiv and its Western allies reject those arguments as a baseless pretext for invasion.
Navalny, who is 45, was jailed last year when he returned to Russia after receiving medical treatment in Germany following a poison attack with a Soviet-era nerve agent.
He blamed the attack on Russian President Vladimir Putin. The Kremlin denies the allegation.
A Russian court last month found Navalny guilty of large-scale fraud and contempt of court, a move likely to extend his time in jail by years. He is able to post content on social media via his lawyers and supporters.
